A surbahar is best described as a bass sitar. This is because it is similar to sitars but larger and tuned between 4 steps and 2 octave lower. Even the technique used for the surbahar is so similar that sitar players have no problems going between the surbahar and sitar.

The surbahar was originally used for the Hindustani classical music from North India. It is over 130 cm (51 inches) long, has a dried pumpkin as a resonator, and a neck made from tun (Cedrela tuna), or teak wood. The combination of the resonator and the long strings allow the surbahar to emit quite low frequencies of less than 20 Hz. There are 4 rhythm strings (cikari), 4 playing strings and between 15 and 17 un-played sympathetic strings. The thickest playing string is up to 1mm in diameter.

One advantage that the surbahar has over the sitar is that it can sustain a note longer and can glissando (meend) an entire octave on one fret. The instrument is quite well suited to long slow alaps. An aplap is the un-metered, improvised section of a typical North Indian classical performance.

The sustain does bring a problem though. When the surbahar is used to play faster North Indian music such as the gat and jhala, the notes become muddy and indistinct. This is why the surbahar is used to play slow music, while the sitar is used to play faster music.

It was generally accepted that the surbahar was first developed in 1825 by Ustad Sahebdad Khan, but recent research debates this. The lesser known Ustad Ghulam Mohammed, a sitarist from Lucknow, might have developed majority of the surbahar.